Help Understanding Some Basics

This is a discussion on Help Understanding Some Basics within the C Programming forums, part of the General Programming Boards category; I just recently bought the book:
Mastering Algorithms with C
A Link to the book
In it, the author provides ...

Help Understanding Some Basics

In it, the author provides code for some basic data structures. I am in the process of transcribing them to my machine using vim. Along the way I am attempting to write some basic programs using these data structures just to test my knowledge and help my understanding more.

However, I have run into a bit of a problem. I am unable to figure out how to use the very first one. I will provide you with the code if you can please explain to me how exactly I am to use these structures. I am a bit new to C, but I am really trying here. Any help would be much appreciated.

I am having a tough time understanding the function pointer concept i suppose. I understand it is a pointer to a function, but the function must have arguments passed to it. What am I supposed to pass to the free() macro to get this to compile and also properly use it when i call list_destroy.